ORGN 15 |
| Chemical proteomics plays a key role in proteomics research (1-2). Our group has been focusing on the development of chiral photoligands that can selectively tag small number of kinases in crude cell lysate (3). Our probes consist of adenine, benzophenone, and biotin tethered through a peptide linker. The adenine directs the ligands toward the ATP-binding sites, Benzophenone serves as the photocrosslinker, and biotin is used for detection and purification of tagged kinases. Using this simple strategy we have recently identified a prototype probe that exhibit selectivity toward lck, a Src-family kinase involved in lymphocyte proliferation and differentiation (4). Our prototype probe exhibited significant selectivity toward Lck both in a mixture of commercial kinases and in a lysate of Jurkat cells (5). Furthermore, it was found that the chirality center at the base of benzophenone plays a critical role in selective lck labeling and that lck recognizes both adenine and benzophenone moieties of the probe. Spectrometric analysis revealed that the probe-binding site on Lck is located within the well conserved region of Src-family kinases. Based on these results we are currently designing a library of higher affinity probes for Lck selective labeling. This presentation will show our ligands design scheme, syntheses, and kinase binding profiles. Structural basis of selective ligand recognition will be discussed based on structure-activity relationship and data from mass spectrometry and molecular modeling analyses. (1) G. C. Adam, E. J. Sorensen, B. F. Cravatt, Mol. Cell. Proteomics, 2002, 1, 718. (2) G. Mitsopoulos, D. P. Walsh, Y. T. Chang, Curr. Opin. Chem. Biol., 2004, 8, 26. (3) A. Kawamura, H. Sagit, Chirality, 2005, 17, 332. (4) E. H. Palacios, A. Weiss, Oncogene, 2004, 23, 7990. (5) S. Hindi, H. Deng, L. James, A. Kawamura, Bioorg.&Med. Chem. Letters, 2006, 16, 5625. |
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Biologically-Related Molecules and Processes
8:00 AM-12:00 PM, Sunday, March 25, 2007 McCormick Place East -- Room E350, Level 3, Oral
Division of Organic Chemistry |